Iranian Border Guard keeps watch at a border post in Milak, south-eastern Iran, near the Afghan border. (AFP)

Four Iranian border guards were injured when an IED exploded at Column No. 86 in the Merjava border area between Iran and Pakistan on Friday.

One source told Fars News Agency, that the attack took place in the city of Zahedan, located in the center of Sistan and Baluchestan province in southeastern Iran, adding that the condition of three of the four border guards injured in the bomb attack is stable.

However, the fourth border guard was transferred to receive treatment in a local hospital.

As of yet, no party claimed responsibility for this attack.

The attacks follow an earlier attack carried out on July 8 in Zahedan, which, according to a statement from the provincial branch of the Islamic Revolution Guards Corps (IRGC), resulted in the death of two police officers following an attack on a police station.

Earlier that day, the prosecutor of Sistan and Baluchestan, Mehdi Shamsabadi, announced that only one police officer died in the attack.

The IRGC statement also underscored that all four members of the terrorist team that attacked the police station were neutralized after they stormed the police station in the early hours of Saturday using grenades.